Star rating: ****
There are times, initially, as the Radio String Quartet Vienna attack the Mahavishnu Orchestra's 1970s jazz-rock with furrowed brow and eyes-closed concentration, when a certain Ukulele Orchestra of Great Britain-factor sidles in.

A string quartet tackling the electric snap-crackle of Celestial Terrestrial Commuters is, after all, as likely a proposition as our ukulele heroes adapting Pink Floyd, and both put a smile on the face. In fact, the Vienna-based quartet often make you smile but it's because they've got so convincingly into the Mahavishnu spirit and because the music, in essence, is so uplifting that smiles of approval are involuntary.

Impersonation would be pointless here and faithful recreation impossible, although a familiar keyboard line or guitar hook, with a reasonable approximation as to tone and timbre, occasionally materialises courtesy of violin or viola. Some pieces are boldly re-imagined. Vital Transformation, for example, emerges as a kind of Indian hoe-down and Thousand Island Park as a mini, Bach-style cello suite.

Only You Know, You Know, given a Steve Reich/ Philip Glass minimalist setting and missing the dynamic staccato chops that punctuate the original's descending riff, leaves a slight feeling of anticlimax. Elsewhere, Dawn's theme swells gloriously, A Lotus on Irish Streams cascades beautifully against a brilliantly effective pizzicato-cum-bowed violin body backbeat, and Meeting of the Spirits, with its scary opening chord sequence, survives a slipping E string's sabotage attempt against its helter-skelter energy rush.

If, above all, the quartet bring out Mahavishnu's melodic qualities, they also - standing cellist Asja Valcic excepted, and the two violinists improvising solos - rock with an intensity in keeping with the original model.